Immunosuppressive human anti-CD83 monoclonal antibody depletion of activated dendritic cells in transplantation.

Current immunosuppressive/anti-inflammatory agents target the responding effector arm of the immune response and their nonspecific action increases the risk of infection and malignancy. These effects impact on their use in allogeneic haematopoietic cell transplantation and other forms of transplantation. Interventions that target activated dendritic cells (DCs) have the potential to suppress the induction of undesired immune responses (for example, graft versus host disease (GVHD) or transplant rejection) and to leave protective T-cell immune responses intact (for example, cytomegalovirus (CMV) immunity). We developed a human IgG1 monoclonal antibody (mAb), 3C12, specific for CD83, which is expressed on activated but not resting DC. The 3C12 mAb and an affinity improved version, 3C12C, depleted CD83(+) cells by CD16(+) NK cell-mediated antibody-dependent cellular cytotoxicity, and inhibited allogeneic T-cell proliferation in vitro. A single dose of 3C12C prevented human peripheral blood mononuclear cell-induced acute GVHD in SCID mouse recipients. The mAb 3C12C depleted CMRF-44(+)CD83(bright) activated DC but spared CD83(dim/-) DC in vivo. It reduced human T-cell activation in vivo and maintained the proportion of CD4(+) FoxP3(+) CD25(+) Treg cells and also viral-specific CD8(+) T cells. The anti-CD83 mAb, 3C12C, merits further evaluation as a new immunosuppressive agent in transplantation.

A comparison of treatment outcomes for moxifloxacin versus ofloxacin/metronidazole for first-line treatment of uncomplicated non-gonococcal pelvic inflammatory disease.

Large randomized controlled trials support the efficacy of moxifloxacin for the treatment of uncomplicated pelvic inflammatory disease (PID). This study compares the clinical outcome and tolerability of treatment with moxifloxacin 400 mg once a day or ofloxacin 400 mg plus metronidazole 400 mg both twice daily in patients diagnosed with PID. A retrospective case-notes review was performed on patients diagnosed clinically with PID before and after local guidelines were changed to recommend moxifloxacin as first-line treatment for uncomplicated PID. Before the guidelines changed, 114/134 (85%) patients received the recommended first-line therapy versus 206/257 (80%) after the change, P = 0.3. There was no difference in the clinical outcomes between the two groups; significant improvement/resolved 77% versus 70%; marginal improvement 3% versus 11%; no change/worse 20% versus 18%, P = 0.14. Moxifloxacin is confirmed to be an effective alternative to ofloxacin/metronidazole for the treatment of PID in a large urban genitourinary clinic setting.

Effects of filter pore size on efficacy of continuous arteriovenous hemofiltration therapy for Staphylococcus aureus-induced septicemia in immature swine.

OBJECTIVE: To evaluate the effect of hemofilter pore size on the efficacy of continuous arteriovenous hemofiltration (CAVH) in improving morbidity and mortality in an immature swine model of Staphylococcus aureus-induced septicemia. DESIGN: Prospective, randomized study with age-matched controls. SETTING: Biomedical research facility. SUBJECTS: Fourteen 4 to 8-wk-old, weaned Poland-China swine, weighing 5 to 10 kg. INTERVENTIONS: Spontaneously breathing, ketamine-sedated swine (4 to 8 wks of age) were given an intravenous lethal dose of live S. aureus. Animals were then filtered with either a 50-kilodalton (kD) pore size filter (control) or a 100-kD pore size filter (experimental). No animals received antibiotics. MEASUREMENTS AND MAIN RESULTS: Physiologic, biochemical, and hematologic parameters were measured in all animals every 1 to 3 hrs. Animals were monitored continuously and survival time (hr) was recorded (permanent survival = 168 hrs/7 days). Animals filtered with the 100-kD filter survived significantly longer than control animals (103 +/- 18 [SEM] vs. 56 +/- 9 hrs). The 100-kD-filtered group had one permanent survivor (168 hrs). Protein concentration of the ultrafiltrate obtained from the 100-kD-filtered animals was eight-fold higher than control ultrafiltrate. The protein removed did not contain a high percentage of albumin (as determined by autoanalyzer methods). No significant differences were seen in any of the other measured parameters. CONCLUSIONS: CAVH significantly improved survival in swine with S. aureus-induced sepsis. The superior performance of the 100-kD filter vs. the 50-kD filter suggests that higher molecular weight mediators that are not removed efficiently by the 50-kD filter may be responsible for the morbidity and mortality seen in this model of sepsis. These mediators may be removed in greater proportion by our customized (100-kD pore size) filter.

Structure and dynamics of pentaglycyl bridges in the cell walls of Staphylococcus aureus by 13C-15N REDOR NMR.

Whole cells and cell-wall fractions of Staphylococcusaureus have been labeled by various combinations of [1-13C]glycine, [15N]glycine, L--6-13C-lysine, L--6-15N-lysine, D--1-13C-alanine, and D--15N-alanine. The resulting materials have been examined using 13C and 15N solid-state, magic-angle spinning NMR techniques including cross-polarization, double cross-polarization, and rotational-echo double resonance. The results of these measurements indicate that the peptidoglycan glycyl bridges are complete (five units long) and form cross-links between three-quarters of all peptide stems. The pentaglycyl bridges are immobilized in lyophilized cell-wall fractions in a compact conformation with inter-residue spacings comparable to those of an alpha helix. The bridges have a similar compact conformation in intact whole cells, regardless of whether the cells have been lyophilized or were hydrated and frozen at -10 degrees C. The bridges are also in a time-averaged compact conformation in whole cells at 0 degrees C but with sizable structural fluctuations associated with local mobility. A small fraction of bridges are in extended-chain conformations.

Comparative mapping in the beige-satin region of mouse chromosome 13.

The proximal end of mouse chromosome (Chr) 13 contains regions conserved on human chromosomes 1q42-q44, 6p23-p21, and 7p22-p13. This region also contains mutations that may be models for human disease, including beige (human Chediak-Higashi syndrome). An interspecific backcross of SB/Le and Mus spretus mice was used to generate a molecular genetic linkage map of mouse chromosome 13 with an emphasis on the proximal region including beige (bg) and satin (sa). This map provides the gene order of the two phenotypic markers bg and sa relative to restriction fragment length polymorphisms and simple sequence length polymorphisms in 131 backcross animals. In parallel, we have created a physical map of the region using Nidogen (Nid) as a molecular starting point for cloning a YAC contig that was used to identify the beige gene. The physical map provides the fine-structure order of genes and anonymous DNA fragments that was not resolved by the genetic linkage mapping. The results show that the bg region of mouse Chr 13 is highly conserved on human Chr 1q42-q44 and provide a starting point for a complete functional analysis of the entire bg-sa interval.

Identification of the murine beige gene by YAC complementation and positional cloning.

The beige mutation is a murine autosomal recessive disorder, resulting in hypopigmentation, bleeding and immune cell dysfunction. The gene defective in beige is thought to be a homologue of the gene for the human disorder Chediak-Higashi syndrome. We have identified the murine beige gene by in vitro complementation and positional cloning, and confirmed its identification by defining mutations in two independent mutant alleles. The sequence of the beige gene message shows strong nucleotide homology to multiple human ESTs, one or more of which may be associated with the Chediak-Higashi syndrome gene. The amino acid sequence of the Beige protein revealed a novel protein with significant amino acid homology to orphan proteins identified in Saccharomyces cerevisiae, Caenorhabditis elegans and humans.

Complementation of the beige mutation in cultured cells by episomally replicating murine yeast artificial chromosomes.

Chédiak-Higashi syndrome in man and the beige mutation of mice are phenotypically similar disorders that have profound effects upon lysosome and melanosome morphology and function. We isolated two murine yeast artificial chromosomes (YACs) that, when introduced into beige mouse fibroblasts, complement the beige mutation. The complementing YACs exist as extrachromosomal elements that are amplified in high concentrations of G418. When YAC-complemented beige cells were fused to human Chédiak-Higashi syndrome or Aleutian mink fibroblasts, complementation of the mutant phenotype also occurred. These results localize the beige gene to a 500-kb interval and demonstrate that the same or homologous genes are defective in mice, minks, and humans.

Adnexal infarction after conservative surgical management of torsion of a hyperstimulated ovary.

OBJECTIVE: To report a case of postoperative necrosis after conservative management of torsion of a hyperstimulated ovary. DESIGN: Case report and literature review. SETTING: Tertiary care center. PATIENT: Infertility patient undergoing IVF-ET. INTERVENTIONS: Detorsion followed by unilateral salpingo-oophorectomy 2 days later. MAIN OUTCOME MEASURE: Postoperative course. RESULTS: Postoperative necrosis after detorsion. CONCLUSIONS: Postoperative necrosis is an uncommon but serious complication of conservative surgical management of adnexal torsion.

Continuous arteriovenous hemofiltration therapy for Staphylococcus aureus-induced septicemia in immature swine.

OBJECTIVES: The goals of this study were: a) to evaluate the efficacy of controlled, continuous arteriovenous hemofiltration in improving morbidity and mortality rates in an immature swine model of Staphylococcus aureus-induced septicemia; b) to determine if ultrafiltrate from septic animals contained mediators that produce pathophysiologic changes observed in untreated S. aureus septic pigs. DESIGN: Prospective, randomized, controlled study with age-matched controls. SETTING: U.S. Department of Agriculture-licensed biomedical research facility. SUBJECTS: Sixty-five weaned Poland-China swine (4 to 6 wks of age; 5 to 10 kg). INTERVENTIONS: Part 1: Animals received a lethal dose of live S. aureus (8 x 10(9) colony-forming units/kg) over 1 hr. The three treatment groups included: hemofiltration group 1 (eight filtered, eight nonfiltered animals), plasma filtration fraction = 5.5%; hemofiltration group 2 (six filtered, six nonfiltered animals), filtration fraction = 16.6%; and hemofiltration group 3 (six filtered, six nonfiltered animals), filtration fraction = 33.4%. A control, nonseptic group of animals (n = 4) was filtered to obtain "clean" ultrafiltrate (hemofiltration group 4). Part 2: Sterile ultrafiltrate concentrate batches obtained from each group of filtered, septic animals were concentrated and infused into healthy, nonseptic pigs (reinfusion groups 1 through 3). MEASUREMENTS AND MAIN RESULTS: Physiologic, biochemical, and hematologic variables were measured in all animals every 1 to 3 hrs. Overall length of survival was also recorded. In hemofiltration groups 1 through 3, filtered animals survived significantly longer than matched, nonfiltered (sham-filtered) animals. Increments in survival time increased directly with filtration fraction. Ultrafiltrate concentrate from septic pigs produced death (LD41) and disease similar to those rates observed in untreated S. aureus-septic pigs. Infusion of clean ultrafiltrate concentrate produced no response. CONCLUSIONS: Continuous arteriovenous hemofiltration significantly improved survival rates in swine with S. aureus-induced sepsis. Resultant ultrafiltrate concentrate contained mediators responsible for some pathophysiologic responses observed in this animal model.

Delayed detection of coarctation in infancy: implications for timing of newborn follow-up.

During a recent 5-year period, 74 patients younger than 6 months of age were diagnosed with coarctation of the aorta. Coarctation was correctly diagnosed in only 22% of patients prior to referral despite readily apparent femoral pulse abnormalities in 86%. Infants whose symptoms were detected between 5 and 14 days of age were significantly more ill than infants outside this age range and had a high mortality rate (25%). The number of associated cardiac defects was not related to the severity of clinical illness in this group, suggesting that closure of the ductus arteriosus is the primary determinate of disease severity. Observations in two patients suggested that a detectable pulse discrepancy occurs between 3 and 5 days postnatally. Upper extremity hypertension was found commonly in infants after 5 days of age despite the presence of congestive heart failure. Earlier detection of coarctation in the newborn requires a diligent cardiovascular and peripheral pulse examination between 3 and 7 days of life, upper extremity and lower extremity blood pressure measurement, and a high index of suspicion.

Cardiac loop ECG recording: a new noninvasive diagnostic test in recurrent syncope.

The most crucial step in diagnosing syncope is determining whether or not an arrhythmia is the cause. A new recording device, the continuous cardiac loop ECG recorder, affords prolonged ambulatory monitoring and can capture the rhythm at the time of syncope. To determine the impact of cardiac loop ECG recorders in diagnosing syncope, we reviewed the records of the first 48 patients referred for cardiac loop recording because of unexplained syncope or presyncope. Previous cardiac studies were nondiagnostic in all patients. In 36% of these patients, loop recording definitively determined whether an arrhythmia was the cause of symptoms. Median duration of monitoring was 28 days, with an average charge of $180 per month. Cardiac loop ECG recording is a convenient, safe, inexpensive, and potentially highly effective means of diagnosing unexplained syncope.

Septic shock: principles of management in the emergency department.

Bacteremia is a potentially serious event which must be recognized early and treated aggressively to prevent progression to septicemia and septic shock. The pathophysiology of septicemia and shock includes inadequate tissue perfusion and oxygenation. Expansion of intravascular volume and pharmacologic cardiovascular support are designed to minimize resulting end-organ injury. Initial antibiotic therapy must be individualized and should include an agent or agents active against the common pathogens encountered in the specific clinical setting. Once the causative organism is isolated, therapy is targeted more narrowly. Despite the availability of a variety of newer antibiotics, the morbidity and mortality of septicemia and septic shock remain unacceptably high. Development of new pharmacologic agents active against the mediators of shock may offer future promise.

Hypercalcitoninemia and hypocalcemia in acutely ill children: studies in serum calcium, blood ionized calcium, and calcium-regulating hormones.

We studied the hypotheses that serum calcium and blood ionized calcium would be low in acutely ill children and would rise with clinical improvement. In 15 children admitted to the pediatric intensive care unit, the blood ionized calcium level was 4.45 +/- 0.06 mg/dl (1.11 +/- 0.015 mmol/L) on entry versus 5.17 +/- 0.03 mg/dl (1.29 +/- 0.01 mmol/L) in control subjects (p less than 0.005), rose significantly on days 2 and 3, and was 5.12 +/- 0.04 mg/dl (1.28 +/- 0.01 mmol/L) at discharge (p less than 0.005). Changes in serum calcium level were similar, whereas serum magnesium and phosphorus levels were normal and did not change. Basal serum parathyroid hormone concentrations were elevated, rose further during the study, and were normal at discharge. Serum parathyroid hormone levels correlated inversely with blood ionized calcium levels, indicating that compensatory hyperparathyroidism occurs with low blood ionized calcium concentrations. Basal serum calcitonin values were evaluated on entry and decreased with clinical improvement. Serum calcitonin levels correlated significantly with low blood ionized calcium levels, indicating that hypercalcitoninemia may play a role in the pathogenesis of hypocalcemia in these children. Urine calcium excretion was not increased in the four children studied. We speculate that with clinical improvement, a rise in serum parathyroid hormone levels and a decline in serum calcitonin levels may help restore normocalcemia in these acutely ill children.

Staphylococcus aureus-induced shock: a pathophysiologic study.

The purpose of the present study was to determine the effects of lethal intravenous infusions of Staphylococcus aureus (SA) in adult dogs. Animals were maintained under anesthesia for 6 hr and observed until death following the 1-hr infusions of SA organisms. Findings unique to SA administration compared to those with Escherichia coli were the absence of significant necrosis of the mucosal intestinal glands of the small and large intestines; widespread intravascular colonization of bacteria in lung, heart, kidney and adrenal tissues often associated with neutrophil sequestration, microabscess formation, and necrosis; relative constant blood pressure, fibrinogen, fibrin degradation products (FDP), serum glutamic pyruvic transaminase (SGPT), blood (serum) urea nitrogen (BUN), creatinine, pH, and PO2, all of which remained relatively unchanged for 6 hr. Rapid early increases were observed in temperature, respiration rate, lactate, and hematocrit, while PCO2, platelet and white blood cell concentrations decreased. Results suggest unique qualitative differences in responses to Staphylococcal-induced shock compared to those caused by gram-negative bacteria.